Answer:
22/10 or 2 and 1/5
Step-by-step explanation:
To find the perimeter, add all sides together. Since it's a rectangle, the other sides are the same measurement as the ones given. Add 3/10, 3/10, 4/5, and 4/5 together. To do this, find a common denominator. The lowest common denominator is 10 so multiply the 4/5 by 2/2 to get the denominator to be 10. Now, add 3/10, 3/10, 8/10, and 8/10. It adds up to 22/10 but if you don't want an improper fraction, simplify it to 2 and 1/5.
He'll get $14.03 because 20.25 is what he gave but it only came up to 6.22 so 20.25-6.22=14.03